Monitor screen goes black but computer still going fine

Otherwise I have had this problem for about 3 weeks. I am on the PC and my monitor goes black.
For about a month the monitor would flicker for maybe once every 2-3 hours. Then the black out started. I have changed the video card and vivaciously changed to another PC. I changed from the surge protector to an outrlet. I still get the same essentially thing. When it happens, the CPU is still going fine but no signal to the monitor. I then have to shut down with the CONTRL, ESC, up arrow, etc. I turn it back on and it's fine again. This may happen once a day or twice a weekend. I am on my PC a lot. What do you think? It is a CRT.
Meanwhile http://kdsusa.com/product_details.asp?prod=169

Monitor screen goes black but computer still going fine

Also i'm pretty sure that monitor was never selled with any of the (small amount of) "PCs" [workstations, really] In addition sold by Silicon Graphics (SGI). However I would thus think it fairly likely that comp.sys.sgi.hardware

My CTX 2085 has done this since I bought it in 1995. Moreover it goes black for a
1/2 second then sarts up again..................two times a week or so.

Seems like stuff with more blacks in them (darks on the screen) will get it going.....................seems to be less common now than when it was new.

my roomy back then thuoght is was a weak signal which would trigger the failure of the video for that second.

I use BNC connectors. this moniutor cost over 1200 bucks when i bought it too.

At the same time sounds like you've a fault in your CRT.

And then probably not the CRT its self, but a fault with the monitor. Don't overlook the obvious either, I've seen this happen when the monitor's power cord wasn't fully plugged into it.